Osteochondroma Presenting as a Calcified Mass in the Sellar Region and Review of the Literature.

Objective Osteochondroma (OC) is the most common benign bone neoplasm. It infrequently occurs in the cranial cavity as a calcified lesion and very rarely presents in the sellar region. The present study summarizes the knowledge about OCs of the sellar region. Methods We searched the literature search for the clinical appearance of OCs and other calcified pathologies occurring in the sellar region. Results A total of 21 English-language articles published from 1961 to 2015 documented cases of calcified lesions in the sellar region including cerebral aneurysm, chondroid chordoma, chondroma, craniopharyngioma, OC, odontome, osteoma, pituitary adenoma, pituitary stone, Rathke cleft cyst, retinoblastoma, schwannoma, and xanthogranuloma. Among them, six were OC cases: three in the parasellar region and three in the sellar-suprasellar region. Patients with sellar-suprasellar OCs presented with visual loss and hypopituitarism; patients with parasellar OCs did not show these symptoms. OCs appeared as irregular and multilobulated calcifications on X-ray and computed tomography. On magnetic resonance imaging, OCs showed variable intensity on T1-weighted sequences and consistently heterogenous intensity on T2. Four patients underwent transcranial tumor resection, and the transsphenoidal route was selected for one. Five of the six resulted in a partial resection or internal decompression with a satisfactory outcome. Conclusions Calcified tumors occurring in the sellar region may be OCs, especially if they appear as irregular multilobulated calcification.

Analysis of neural crest cells from Charcot-Marie-Tooth disease patients demonstrates disease-relevant molecular signature.

Charcot-Marie-Tooth disease (CMT) is the most common inherited neuropathy. The majority of CMT is demyelinating type (demyelinating CMT) caused by Schwann cell involvement. Although a large number of genes responsible for demyelinating CMT have been found, the common molecular target of the pathophysiology caused by these different genes in demyelinating CMT is still unknown. We generated induced pluripotent stem cells (iPSCs) from healthy controls and patients with demyelinating CMT caused by duplication in peripheral myelin protein 22 kDa (PMP22) or point mutations in myelin protein zero (MPZ) or early growth response 2 (EGR2). iPSCs were differentiated into neural crest cells, progenitors of Schwann cells, followed by purification using the neural crest cell markers p75 and human natural killer-1. To identify a disease-relevant molecular signature at the early stage of demyelinating CMT, we conducted global gene expression analysis of iPSC-derived neural crest cells and found that a glutathione-mediated detoxification pathway was one of the related pathways in demyelinating CMT. mRNA expression of glutathione S-transferase theta 2 (GSTT2), encoding an important enzyme for glutathione-mediated detoxification, and production of reactive oxygen species were increased in demyelinating CMT. Our study suggested that patient-iPSC-derived neural crest cells could be a cellular model for investigating genetically heterogeneous disease CMT and might provide a therapeutic target for the disease.